Multiple choice Which city in Uttar Pradesh, sets the Indian Standard Time (I.S.T.) ? Lucknow Allahabad Varanasi Gorakhpur Reveal answer Fill a bubble to check yourself B Correct answer Explanation Indian Standard Time is calculated from the longitude 82.5°E, which passes through Allahabad (now Prayagraj). The Indian Time Standard meridian runs near the Allahabad Observatory. IST is UTC+5:30, making it 5.5 hours ahead of Greenwich Mean Time.